Teach Yourself Borland C++ in 14 Days - portal

SYNTAX
Wading In Deeper
immediately following the loop code block. The exception to this description is the do-while
loop, which tests for the condition at the bottom of the loop rather than at the top.
The test condition tells the loop when to stop executing. In effect the test condition says, for
example, “Keep doing this until x is equal to 10,” or, “Keep reading the file until the end-offile
is reached.” Once the loop starts it continues to execute the body of the loop until the test
condition is met.
WARNING
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TIP
It’s easy to accidentally write a loop so that the test condition is never
met. This will result in a program that is locked up or hung. Your only
recourse at that point is to press Ctrl+Alt+Del and kill the task. The
Windows Close Program box will come up and will display the name
of your program with (Not Responding) next to it. You’ll have to select
your program from the list and click End Task to terminate the
runaway program.
In C++Builder you typically run a program using the Run button on
the Speed Bar or by pressing F9. If you need to kill a runaway program
that was run from the IDE, you can choose Run | Reset Process from
the main menu or press Ctrl+F2 on the keyboard.
Given that general overview, let’s take a look at each type of loop individually.
The for Loop
The for loop is probably the most commonly used type of loop. It takes three parameters:
the starting number, the test condition that determines when the loop stops, and the
increment expression.
The for loop statement:
for (initial; cond_expr; adjust) {
statements;
}
The for loop repeatedly executes the block of code indicated by statements as long as the
conditional expression, cond_expr, is true (nonzero). The state of the loop is initialized by
the statement initial. After the execution of statements, the state is modified using the
statement indicated by adjust.
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